Servicing a plurality of well tubings



Jan. 16, 1968 w. F. BOHLMANN, JR

SERVICING A PLURALITY OF WELL TUBINGS Filed Oct. 18, 1965 l N VEN TOR.

WILLY F. BOHLMANN, JR.,

f CARRIER W-T' -CHOKE United States Patent 3,363,693 SERVICING APLURALITY 6F WELL TUBINGS Willy Frank Bohlrnann, Jr., Sydney, Australia,assignmto Esso Production Research Company Filed Oct. 18, 1965, Ser. No.497,113 16 Claims. (Cl. 166-45) ABSTRACT OF THE DISCLOSURE At least twowell tubings are serviced from a single pipe string connected to both ofthe tubings through a common selectively prcssure-closeable connection.

The present invention is directed to a method for serving a well. Inparticular, the invention is concerned with servicing a well having aplurality of well tubings arranged therein. In its more specificaspects, the invention is concerned with servicing a well provided witha plurality of well tubings through one pipe string.

The present invention may be briefly described as a method of servicinga plurality of well tubings from a single pipe string. In the presentinvention, at least two well tubings are arranged in a well with a pipestring being connected to both of the tubings to provide service to thetwo well tubings. The pipe string is connected to both of the wellsthrough a common connection which is selectively closeable underpressure such that each tubing may be selectively closed off. Fluid isflowed through at least one of the tubings under pressure and theconnection is closed to a selected one of the tubings by controlling thepressure.

In the present invention, fiuid is flowed upwardly or downwardly in thetubing string. The fluid may be a workover fluid, such as oil, water,emulsion of oil and water, acid, hydrocarbon, such as oil and/ or gasproduced from the well from a subsurface formation in fluidcommunication with at least one of the tubings, or it may be a slurry ofcement or any other fluid or suspension which is used in welloperations.

The present invention also comprises apparatus for servicing a pluralityof well tubings from a single pipe string. At least two well tubings arearranged in a well in the present invention and a crossover connectingmeans connects a single pipe string to each of the tubings and to eachother. The cross-over connection means has a first passageway to one ofthe tubings and a second passageway to the second of the tubings, eachof the passageways opening into the cross-over connection means and theopenings form or provide a valve seat. Valve means in the cross-overconnection means is provided which is adapted to seat on the valve seatand close a selected one of the passageways by imposition of acontrolled pressure in one of the tubings.

The first and second passageways may be of diiierent diameters such thatthe valve means will seat selectively on one or the other of the valveseats to close off one of the passageways.

The valve means may suitably be a sleeve valve operated by differentialpressure to close selectively the one of the two passageways or anyother valve which is operable by differential pressure.

The present invention will be further illustrated by reference to thedrawings in which:

FIGURE 1 is a cross-sectional view showing a valve closing one of thetubing strings;

FIGURE 2 is a cross-sectional view of the cross-over connection means ofFIGURE 1;

FIGURE 3 is a cross-sectional view showing the valve closing off asecond tubing string; and

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FIGURE 4 is a cross-sectional view of the cross-over connection means ofFIGURE 3.

Referring now to the drawing in which a best mode and embodiment are setforth, and particularly to FIG- URES 1 and 2, 11 designates a wellcasing cemented in a well drilled in water bottom 14 of a body of water15. While the invention has been described and illustrated with respectto wells drilled at water locations, it is equally applicable to wellsdrilled on land or by other means than those described herein. The wellcasing 11 has a first tubing string 16 and a second tubing string 17arranged therein. The tubing strings 16 and 17 have lower ends 18 and 19respectively which terminate with respect to tubing string 16 in thespace 20 isolated between packers 21 and 22 and communicate byperforations 23 with upper hydrocarbon productive zone 24. The tubingstring 17 communicates by perforations 25 with a lower hydrocarbonproductive zone 26.

The tubing strings 16 and 17 extend into a Christmas tree (not shown)adacent water bottom and to which is connected flow lines 27 and 28,flow line 27 communicating fluidly with tubing string 16 to form aconduit therewith and flow line 28 communicating fluidly with tubingstring 17 to form a conduit therewith.

Tubing strings 16 and 17 are interconnected by a crossover means 29shown more clearly in FIGURE 2. Cross over connection means 29 isprovided with a common passageway 30 which communicates with tubingstring 16 by passageway 31 and with tubing string 17 by passageway 32.It is to be noted that the passageway 31 is larger than the passageway32. A ball valve 34 or other valve such as a differential pressureoperated valve is arranged in the passageway 30 for seating on seat 35-is passageway 31 or on seat 36 in passageway 32. Thus, if a pressuredifferential exists between upper zone 24 and lower zone 26, one or theother of the passageways 31 or 32 will be closed depending on thepressure. Likewise, by imposing a pressure diiferential on tubingstrings 16 or 17 by external means, such as from the surface, the ballvalve 34 may be closed to seat selectively on one or the other of theseats 35 or 36. It is to be noted that a pipe string 37 connects to thecross-over connection means and to passageway 30 therein. This pipestring 37 extends to above the water surface 38 and is closed by a valve39. Likewise, the flow lines 27 and 28 are also closed respectively byvalves 40 and 41.

In the operation of FIGURES 1 and 2 wherein it is desired to installequipment in tubing string 17, production would be stopped in tubingstring 16 by closing valve 40. Fluid would be pumped down the how line28 to pump the pump-down tool carrier 42 carrying a suitable tool suchas a storm choke 43 for landing in the landing nipple 44. Since thepressure in tubing string 17 is greater than that exerted from the upperzone 24 in tubing string 16, the ball valve 34 seats on the seat 35 andcloses the tubing string 16 allowing the service fluid to flow to thesurface through the pipe 37.

With reference to FIGURES 3 and 4, if it is desired to remove a stormchoke such as 43 which has been seated in the landing nipple 45 oftubing string 16, a similar procedure would be employed. It is notedthat a storm choke 48 is seated in landing nipple 44 of tubing string17. In this instance, the pump-down tool carrier 42 would first bepumped down in tubingstring 16 as has been described with reference toFIGURES 1 and 2 and latched onto the storm choke 43 thereafter with thevalve 41 in flow line 28 closed and valve 33 in pipe 37 open as inFIGURES 1 and 2. Fluid would be flowed down the pipe 37 against thepump-down tool carrier which would unseat the storm choke 43 fromlanding nipple 45. The ball valve 34 or diiferential operated valve, byvirtue of the pressure in tubing string 16 being greater than thepressure in tubing string 17 from zone 25, would cause the flow to beupward in tubing string 16 with the valve 34 seated on the seat 36.

Thus, in accordance with the present invention, the cross-overconnection means is selectively closed to one of the tubing strings bycontrol of pressure in another of the tubing strings.

The tubing strings 16 and 17 are provided with landing nipples 46 and 47respectively. These landing nipples may be utilized for receiving plugswhich may be removed by imposing a high pressure in the respectivetubing strings to cause them to be forced outwardly from the respectivetubing string; or the plugs may be retrieved by employing a pump-downtool provided the pump-down tool has a sufficient length to extend abovethe cross-over connection means such that it may be removed by fluidpressure.

In accordance with the present invention, production may be continued inone tubing while the other is being serviced. Thus, during servicingoperations in tubing string 16 with fluid pressure being flowed downpipe string 37, a pressure greater than that exerted in tubing strings16 and 17 is exerted on the ball valve 34 (or differential operatedvalve) which causes it to seat on seat 36. Production is thus continuedin tubing string 17. The reverse may obtain when servicing takes placein tubing 17 with production being continued in tubing string 16. Whenservicing is not being conducted in either tubing string 16 or 17, thevalve 34 closes the passageway which is designed to be closed at thehigh pressure. During production through both tubing strings 16 and 17,valve 39 remains closed.

The present invention is quite useful and advantageous in that inaccordance with the present invention method and apparatus are providedwhereby a single pipe string may be employed to service a plurality oftubing strings. Heretofore in submarine wells, particularly, it has beennecessary to provide a pipe string to service each producing string. Inaccordance with the present invention where a tubing string isselectively closed off by control of fluid pressure, it is unnecessaryto provide more than one pipe string to service a plurality of tubingstrings.

While the present invention has been illustrated in installing andremoving a storm choke, the invention is not to be limited thereto sinceit is applicable to installation and removal of any type of pump-downtool.

The pump-down tool carrier is a tool carrier which has flexibility or isarticulated such that it can move around curves and bends in tubing andin flow lines such as are used on wells completed onbottom of a body ofwater.

Thus, in accordance with the present invention, by controlling fluidpressure in one tubing string, the other tubing string is selectivelyclosed ofi" such that the pipe string may be used for servicing theother tubing string. The connection to the tubing string may be sizedsuch as to provide a pressure differential or a different pressure maybe imposed where the passageways are of the same or substantiallyidentical diameters. Likewise, while a ball valve has been illustrated,all types of valves may be used which will work on differentialpressure.

The nature and objects of the present invention having been completelydescribed. and illustrated and the best mode and embodiment contemplatedset forth, what I wish to claim as new and useful and secure by LettersPatent is:

1. A method of servicing a plurality of well tubings from a single pipestring in which at least two well tubings are arranged in a well withsaid pipe string being connected to both of said well tubings through acommon selectively pressure-closeable connection and in which fluid isflowed through at least one of said tubings under pressure whichcomprises closing the connection to a selected one of said tubings byselectively controlling said pressure.

A method in accordance with claim 1 in which said fluid is flowedupwardly in said one of the tubings.

3. A method in accordance with claim 1 in which said fluid is floweddownwardly in said one of the tubings.

4. A method in accordance with claim 1 in which the fluid is a workoverfluid.

5. A method in accordance with claim 1 in which the fluid is producedfrom a subsurface formation in fluid connection with said one of thetubings.

6. A method of servicing a plurality of well tubings from a single pipestring in which at least two well tubings are arranged in a well withsaid pipe string being connected to both of said well tubings through acommon valved connection selectively closeable under pressure and inwhich fluid is flowed through at least one of said tubings underpressure which comprises selectively controlling said pressure wherebysaid valved connection to a selected one of said tubings is closed.

7. A method of servicing a plurality of well tubings from a single pipestring in which at least two well tubings are arranged in a well withsaid pipe string being connected to both of said well tubings through anormally open common connection which is selectively closeable to eachtubing by a selected pressure and in which fluid is flowed through atleast one of said tubings under pressure which comprises controllingsaid pressure whereby said connection to a selected one of said tubingsis closed.

8. A method of servicing a plurality of well tubings from a single pipestring in which at least two well tubings are arranged in a wellcommunicating with a plurality of hydrocarbon productive formations atdifferent pressures with said pipe string being connected to both ofsaid well tubings through a common connection selectively closeableunder pressure and in which fluid is flowed through at least one of saidtubings under pressure from one of said formations which comprisesimposing said pressure selectively on said connection whereby saidconnection to the other of said tubings is closed.

9. A method of servicing a plurality of well tubings from a single pipestring in which at least two well tubings are arranged in a well with.said pipe string being connected to both of said well tubings through acommon connection selectively colseable under pressure and in whichfluid is flowed first through the first of said tubings under pressurewhich comprises closing the connection to the second of said tubings bycontrolling pressure, and then flowing fluid through the second of saidtubings at a different pressure whereby the connection to the second ofsaid tubings is opened and the connection to the first of said tubingsis closed.

10. A method of servicing a plurality of well tubings from a single pipestring in which at least two well tubings are arranged in a well withsaid pipe string being connected to both of said well tubings through acommon connection selectively closeable under pressure which comprisesflowing fluid through a first of said tubings under a first pressure toclose the connection to a second of said tubings, adjusting said fluidpressure to open the connection to said second tubing and to close theconnection to the first tubing and then flowing fluid through the secondtubing. I 11. Apparatus for servicing a plurality of well tubings irom asingle pipe string in which at least two well tubings are arranged in awell, which comprises a cross-over connection means connecting said pipestring to each of said tubings and connecting said tubings to eachother, said cross-over connection means having a first passageway to oneof said tubings and a second passageway to a second of said tubings,each of said passageways opening into said cross-over connection meansand each of said openings being formed to provide a valve seat, andvalve means in said cross-over section means adapted to seat on saidvalve seats and close a selected one of said passageways by impositionof a controlled pressure in one of said tubings.

12. Apparatus for servicing a plurality of well tubings from a singlepipe string in which at least two well tubings are arranged in a Well,which comprises a crossover connection means connecting said pipe stringto each of said tubings and connecting said tubings to each other, saidcross-over connection means having a first passageway to one of saidtubings of a larger diameter than a second passageway to a second ofsaid tubings, each of said passageways opening into said crossoverconnection means and each of said openings being formed to provide avalve seat, and valve means in said cross-over section means adapted toseat on said valve seats and close a selected one of said passageways byimposition of a controlled pressure in one of said tubings.

13. Apparatus for servicing a plurality of well tubings from a singlepipe string in which at least two well tubings are arranged in a Well,said well tubings and said pipe string each having a valve means tocontrol flow of fluid, which comprises a cross-over connection meansconnecting said pipe string to each of said tubings and connecting saidtubings to each other, said cross-over connection mean having a firstpassageway to one of said tubings and a second passageway to a second ofsaid tubings, each of said passageways opening into said cross-overconnection means and each of said openings being formed to provide avalve seat, and valve means in said cross-over connection means adaptedto seat on said valve seats and close a selected one of said passagewaysby imposition of a controlled pressure in one of said tubings.

14. Apparatus in accordance with claim 13 in which the valve means is aball valve.

15. Apparatus in accordance with claim 13 in which the valve means is adifferential pressure operated valve.

16. Apparatus for servicing a plurality of well tubings from a singlepipe string in which at least two well tubings are arranged in a well,which comprises a cross-over connection means connecting said pipestring to each of said tubings and connecting said tubings to eachother, said cross-over connection means having a first passageway to oneof said tubings and a second passageway to a second of said tubings,valve means in said cross-over connection means adapted to close aselected one of said passageways by imposition of a selected controlledpressure in one of said tubings.

References Cited UNITED STATES PATENTS 2,852,079 9/1958 Hebard 166-52 X3,040,813 6/1962 Tausch et al 166-45 X 3,064,580 11/1962 Calvert et a1.166-45 X 3,172,469 3/1965 Coberly et al 166-45 X 3,322,192 5/1967Woelfel et al. 166-224 X CHARLES E. OCONNELL, Primary Examiner. DAVID H.BROWN, Examiner.

